The generation of airborne contaminants generated during cleaning, coating, refurbishing and similar operations is often accompanied by the necessity of controlling the contaminants to reduce or eliminate damage to the environment and to not compromise the safety of workers operating in the operational environment. Often these needs are met by the construction of complex systems that filter or divert contaminants to waste collection points for removal offsite. In other cases, complex systems filter contaminants which are then expelled through ducts or stacks to the outside of the environment. In some situations, operations are required to be performed outside buildings to be sure contaminant concentrations do not reach beyond governmental safety limits. These solutions are often expensive and require permanent locations, thus requiring the movement of the items (“work pieces”) to be cleaned or otherwise treated to be moved to a separate cleaning facility.
In addition, numerous factories and fabrication facilities manufacture more than one type of item. Often, these items may vary in size and the actual location in the facility where they are manufactured and/or conditioned, e.g. cleaned or painted, may be different for different products. Thus, it would be beneficial to utilize a contaminant control system that could be moved to different locations, sized for different needs, and not require complex ducting or waste treating components to safely contain or remove the airborne contaminates generated during the treatment process.
Finally, workers are often needed to perform the work of cleaning, refurbishing, etc. the various work pieces. It is desirable to reduce or eliminate worker exposure to particulates generated from the work piece and cleaning materials during these operations.
There have been previous attempts to create contaminant control systems that are safe for workers, do not harm the environment, and are efficient to use. U.S. Pat. No. 7,134,444 to Mintie, et al. discloses a portable and collapsible environmental containment unit that includes a HEPA filter intake unit and vacuum to draw intake down and out of the unit to create negative pressure within the collapsible containment unit. However, workers within the unit are exposed to any contaminants that are generated. In addition, contaminants are drawn into a closed container that require disposal.
U.S. Pat. No. 3,370,404 to Leeper discloses an air cleaner the can be attached to the doors of an automobile paint booth. The cleaner is not mobile and utilizes a bent air passage with several inclined fins to create a zigzag course for incoming air through a water filter. However, the air cleaner makes no provision for control of contaminants generated within the attached paint booth itself.
European Patent No. 0016698 to Budzinski shows a paint booth that utilizes a laminar flow air stream to surrounds the work piece being painted and form a circulation around the work piece. The air is exhausted downward through ducts underneath the booth. However, ducts are required to remove the exhaust from the workplace and the '698 patent makes no provision for utilizing the disclosed system with work pieces of different sizes or numbers.
Therefore, there exists in the field a need for a mobile airborne contaminant control system that can be moved to various locations with a facility, provide a safe environment for people working within the contaminant control system, and reduce or eliminate the amount of contaminated effluent air exiting the system.